The problem is that they would have to do something with a ver different spin on it. As they did Apocalypse world where most of characters where a mirror verse version of themselves. They now done Dean in a world in a delay time. So what verse would they do? An alternative world is only way to bring back Cas and others that are “Dead” as they have said. So as long as it Supernatural in nature and same interesting stories with a twist to make alternative world a useful plot point not just a device to have season 16 then go for it 😀